Timer



Nov. 6, 1923.'

R. C. CLARKE TIMER Filed March 3. 1921 Patented Nov. 6, 1923.

UNITED STATES PATENT OFFICE ROBERT C. CLARKE, or LAUREL, NEW YonK.

TIMER.

. Application filed March 3, 1921. Serial No. 449,306.

In my improved timing device the rotor,

which is carried by an engine driven shaft,

and which is provided with a peripheral contact, is revoluble in constant engagement with the several individual spring contact elements whichrepresent the ignition circuits for the different cylinders, whose pressure upon the rotor contact,to close the respective ignition circuits, occurs througha smoothly guided or wiping co-action between said rotor contact and said spring contacts without shock or jar such as would tend toward excessive wear in operation.

Further, by according a curvature to that portion of the spring contact which is to co-act with the rotor contact, a dwell surfaceis provided which prolongs the periodv of excitation for the individual cylinder ignition circuits. This is of particular importance where the electrical discharge flows from spark coils having vibrators as will be v readily appreciated The rotor, which is composed of suitable nsulation material, as fibre for example, may be provided with peripheral, anti-frictional means to avoid undue wear between said rotor and the spring contacts with which it is in constant revoluble engagement.

/ Other features and advantages of my in-V vention will hereinafter appear In the drawing Figure 1 a side sectional elevation of my improved timer. 7

Fig. 2 is a front section on the line 2--2 of Figure- 1.

Fig. 3 is a cross-section through the rotor,

and

Fig. 1 is a side elevation of the rotor.

In the example of my invention illustrated in the accompanying drawing, let 1 indicate .he usual timing shaft of an internal combus- 56 tion engine, and 2 a rotor element, composed of fibre or some other suitable insulating material, said rotor having a slot 3 for the reception of a pin 4 that is entered in an orifice provided therefor in shaft 1, to key the rotor to the shaft; and said rotor having a partly cylindrical groove 5 formed transversely therein, open at one end and exposed through the peripheral surface of said rotor.

Said groove 5 is intended for the reception of a cylindrical contact element 6, which fits snugly therein, but is capable of rotation for purposes of adjustment. A surface portion of contact 6 protrudes through the peripherall ex )osed ortion of roove 5 to thus be in position for service. The contact 6 has a diminished end portion 7 that projects beyond the end of the rotor, and a disk 8, that fits over shaft 1, has an orifice 9 to receive end portion 7 and electrically engage it and the unreduced end surface of said contact,

also securing the latter in its operative position within the rotor. Also disk 8 is provided with an orifice 9 for the engaging reception on an angled portion of pin 41. Thus the disk 8 comprises a localizing cap for contact 6 and pin 41, and is itself secured upon the shaft by a nut 9". i

The timer casing is in two parts 10 and 11, which are capable of removably fitting together in any known manner. The part 10, which may be provided with a control fitting 12, has secured tlierein a number of spring contact elements 13, each connecting with a separate binding post 14, and adapted to successively effect a wiping contact with ele iment16, lVhile four of these spring contact elements 13 are herein shown, this is of course a purely arbitrary number thereof, for use-with the ignition circuits, respectively, of an engine having four cylinders, and the number of said elements 13 may be varied at will.

The elements 13 extend inwardly of casing part 10 from its inner peripheral surface, each lying in irregular tangents from a bend 15, that springs from a flat portion 16 which engages a binding post 14:- Said portion 16. is seated in a recess 17 provided in an insulation piece 18 that is secured, by the securing means for the binding post, to the I wall of the casing portion 10, this seating re lation of the elements 13 serving to localize them, and prevent their being accidentally shifted out of the operative transverse plane they occupy.

The spring contact elements 13 are angled so that they unitedly form an outer ill bearing for rotor 2, upon whose peripheral surface the free end portions of-said elements continually bear, for guidance into contact with element 6, successively, in the rotation of the shaft.

Each spring contact element 13 is provided with a curved portion 18, adapted to prolong the period of passing contact ef tected by member 6, said curvature 18 enabling the element 6 to meet elements 13 at a point in advance of the point of contact which would occur it the contact. por tion of elements 13 were flat, and correspondingly, the element 6 does not leave electrical engagement with elements 18 until it has passed beyond said curved por tion 18. This feature is of especial importance where a vibrator controlled coil is used and the discharge at the spark points continues through the period or excitation.

Due to the continual. engagement of elements 1-3 with the rotor and the easy gradient with which portions l8" enter upon their contacting relation with element (5, the life of the device is prolonged, because only a minimum of wear can occur between the parts. Besides, the action is that oi a wip .ing contact, which is highly elticient.

As the used surface of element 6 wears said element can be rotated slightly in its bearing, to present'a new contact portion. For this purpose the end of portion '7 may have an exposed nick 19 for engagement by a small tool, whereby said element (5 may be rotated without removal of disk 8.

The rotor 2 is provided with a peripheral groove 20, which may be filled withsoine lubricatingmaterial, indicated at 2i, such as grease, rawhide, or ,other suitable substance, to minimize :triction between the ro tor and spring contacts in the operation of the device.

Variations within the spirit and scope of my invention are equally comprehended herein.

spring contact elements centering from said casing in' bearing relation with said ro tor, said spring contact elements having curved bearing surfaces to eltect prolonged engagement with said rotor contact.

2. A timer comprising a shatt, a rotor of insulation material carried thereby, said rotor having a partly cylindrical, transverse peripheral groove, a cylini'lrical contact element fitted in said groove and projecting fl'Oni the peripheral surface of the rotor, a casing, and a number of spring contact ele ments carried by said casing, said. spring contact elements bearing normally against said rotor to successively ngage said cylincylindrical contact element titted in said groove and projecting from the peripheral surface of the rotor, a casing, and a number of spring contact elements carried by said casing,- said spring contact elen'ients bearing normally againstsaid rotor to successively engage said cylindrical contact element with wiping contact.

4-. A timer comprising a shaft, a rotor o't insulation material carried thereby, said rotor having a partly cylindrical, transverse peripheral groove, a contact element reinovably fitted within said groove and having a segn'iental operative portion projected beyond the peripheral surface of said rotor, a casing, a number of spring contact elements centering tangentially :trom the peripheral wall of said casing and bearing normally against said rotor, said spring contact elements each having a curved bearing surface to co-act with the segmental operative portion of said rotor contact element and el'l'ect prolonged passing contact therewith.

5. The combination, in a timer, of a rotor composed of insulation material, said rotor having a partly cylindrical, transverse periphe 'al groove, a contact element titted in said'groove and projecting from said rotor, a number of spring contact elements bearing continually upon said rotor. and said rotor having a peripheral groove containing lubricating material. to minimize friction between said rotor and contact springs.

Signed at the borough of illanhattan, in the city, county and State of -i\ e\v York, this 26th day of February, A.' D. v1072i.

ROBERT 0/ CL A RKE,

Il (ll) llll 

